I have been using BareTail for low-footprint log reading, and it works wonderfully. In particular, I like that it can consume very large large files, detect changes to those files, all without consuming much memory at all.

I'd like to know if there are applications out there -- flash, java applet, etc -- that I could use in a web page to mimic this functionality in a program I'm writing.

What I hope to achieve is the ability to consume log files on a server inside the firewall and display them on a web page, in a semi-streaming fashion. As I said, I'd essentially like to have BareTail in a browser

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Tailon is a simplistic web interface to tail -f and tail -f | {grep,awk,sed}. In this regard, it is very similar to clarity (I wrote tailon as a safer and more modern alternative to clarity). Log.io is another modern log file viewer that fits your description.

The simplest and most common way to send discrete items of news to a browser is an RSS feed. A javascript feed parser should sort it out. Or just use an aggregator server-side. Depends on your exact needs really; you'd be better posting a description of what you're trying to achieve, rather than how you think you'll achieve it.

Edit: thanks for the update. For what you want, I'd suggest using something like rsyslog to log into a mysql database, and then just having a php script to query the latest records, and print them, generating an HTML or RSS file. rsyslog should maintain the database nicely (maybe with the help of cron jobs), and any decent distro will have packages which sets most of this up for you.

thanks for the thoughts, Lee. I'm sure I could whip up a program myself to do this without much fuss. I was really looking for pre-built, drop-in solutions if they existed. I'm finding though that such an application probably does not exist, and I'll need to roll one.
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marc esherOct 30 '09 at 21:49

I needed something like this a couple years back, and didn't find anything that fit well. I ended up writing a simple AJAX loop on the client requesting data including a token from the previous response and appending it to the page. This was paired with a script on the server returning data starting from the file position determined by that token.